Graphene oxide (GO) nano-powder is synthesized by the modified Hummer's method, and further thin films are deposited by using the water solution of GO through spin-coating. These films are thermally reduced along with the synthesized GO nano-powder at 50 to 200 °C in a high vacuum. Microstructural, electrical, and optical properties are expectedly controlled by thermal reduction. The electronic properties of GO are investigated by X-ray photoelectron spectroscopy and near-edge X-ray absorption fine structure. The reduction is confirmed by Raman spectroscopy. The work function and band gap of GO are tuned with the thermal reduction. The changes in properties of GO are not linear, and anomalous changes are observed for the reduction around 150 °C. Pristine and reduced GO nano-powder is incorporated into TiO 2 paste to be the photoanode for dye-sensitized solar cells (DSSCs). It is observed that the performance of the fabricated cells is significantly enhanced for the GO reduced at 150 °C, and the cell exhibited a significant increment of ∼23% for the power conversion efficiency in comparison to DSSC based on an unmodified TiO 2 photoanode.

The use of ZnTe as the buffer layer in the Cu 2 ZnSnS 4 (CZTS) based solar cells showed the improvement in overall e ciency. It may also reduce the overall cost of these cells as both the layers (absorbing and buffer) are having eco-friendly and earth abundant constitutes. The sol-gel spin coating method is used for the deposition of CZTS thin lms on the corning glass substrates. The X-ray diffraction studies showed the peaks corresponding to (112), ( 200), ( 220) and ( 312) planes which con rmed the formation of essential kesterite phase. The optical band gap of the deposited lms was found around 1.9 eV by UVvisible spectrophotometer. The optimum thickness of the absorber layer was investigated based on the performance of ZnO:Al/ZnO/ZnTe/CZTS/Mo cell structure by using AMPS-1D simulation tool, while the tool was moulded by the investigated data from the sol-gel deposited CZTS thin lms. The e ciency of solar cell was found to be increased till 22.64% with increment in the thickness of absorber buffer layer up to 2500 nm and beyond this it starts to decrease. In addition to this, it was also analysed that the current density is improved with operating temperature as it is one of the requirements in the high solar radiation areas where the temperature rise more than 50 C in summer.

Organic pollutant and dyes released into the environment by industries have been highly harmful and toxic for humans as well as for the environment. Graphene oxide (GO) and its reduction form, one of the allotropes of carbon family, were investigated for the removal of pollutant dyes. GO nano-powder was synthesized using an improved version of Hummer’s method and further thermally reduced at different temperatures 125, 150, 175, and 200 °C in the vacuum ambient. An intense (002) diffraction peak was observed at 2θ=9.136° for the pristine GO in the X-ray diffraction spectra which is gradually shifted towards the higher angles with the reduction, and it disappeared if the GO sample reduced at 200°C. I D /I G ratio for GO nano-powder in the Raman spectra decreased from 0.94 to 0.76 due to reduction. GO shows a characteristic absorption band at 3395 cm -1 in Fourier transform infra-red spectra corresponding to stretching of hydroxyl (–OH) group, this peak is flattened with the thermal reduction but not eliminated completely. The band gap of pristine GO significantly reduced from 2.31 to 0.73 eV with the reduction as measured by UV-Vis diffuse reflectance spectrophotometer. Dye adsorption and photocatalytic degradation behaviour of the pristine GO and reduced graphene oxides (rGOs) was examined towards methylene blue dye for 10 mg of GO/rGOs powder in 50 ml of 50 ppm solution by UV-Vis absorption spectroscopy. Pristine GO showed potential adsorption capacity and dye was degraded up to 85.78% within 15 minutes and around 97% after 4 hrs. Meanwhile, highest 47.58% photocatalytic degradation of Methylene blue was achieved for the rGO sample reduced at 150°C in the presence of visible light of 100 watt.

The use of ZnTe as the buffer layer in the Cu2ZnSnS4 (CZTS) based solar cells showed the improvement in overall efficiency. It may also reduce the overall cost of these cells as both the layers (absorbing and buffer) are having eco-friendly and earth abundant constitutes. The sol-gel spin coating method is used for the deposition of CZTS thin films on the corning glass substrates. The X-ray diffraction studies showed the peaks corresponding to (112), (200), (220) and (312) planes which confirmed the formation of essential kesterite phase. The optical band gap of the deposited films was found around 1.9 eV by UV-visible spectrophotometer. The optimum thickness of the absorber layer was investigated based on the performance of ZnO:Al/ZnO/ZnTe/CZTS/Mo cell structure by using AMPS-1D simulation tool, while the tool was moulded by the investigated data from the sol-gel deposited CZTS thin films. The efficiency of solar cell was found to be increased till 22.64% with increment in the thickness of absorber buffer layer up to 2500 nm and beyond this it starts to decrease. In addition to this, it was also analysed that the current density is improved with operating temperature as it is one of the requirements in the high solar radiation areas where the temperature rise more than 50ᵒC in summer.

Background: Malnutrition and tuberculosis are both problems of considerable magnitude in most of the underdeveloped regions of the world. Magnesium ion concentration of blood is inversely proportional to the type and extent of the disease which could possibly be due to chronic malnutrition and the amount and destruction of lung tissue in cases of pulmonary tuberculosis. This study is to see the effect of mycobacterium tuberculosis infection and antituberculosis treatment on serum magnesium level. Material & Methods: A hospital based longitudinal case control study done on all outdoor and indoor diagnosed patients of Pulmonary Tuberculosis (PTB), Multidrug-resistant Pulmonary Tuberculosis (MDRPTB) and healthy controls in IRD, Jaipur. 56 diagnosed cases of pulmonary tuberculosis before starting treatment (group PTB at initial) were followed after 2 months of treatment (group PTB at the end of intensive phage). 56 diagnosed case of multi drug resistant pulmonary tuberculosis (group MDRPTB). 56 age and sex matched healthy controls were taken and every candidate was examined for serum magnesium. Results: Our study showed that the maximum numbers of patients (54.76%) were in the age group of 31-50 years, male preponderance (57.14%). It was observed that Mg++ levels were signicantly decreases in PTB and MDRPTB cases as compared to control group. The Mg++ levels were also found to be signicantly lower in MDRPTB patients as compared to PTB patients (p=0.0047*). The mean value of serum magnesium level was signicantly lower in malnourished patients (1.575±0.012 mg/dl) compare to normal BMI patients (1.585±0.011 mg/dl), (p-value<0.001*) and was statistically signicant at initial in PTB group. The comparison of type of lesion & severity of disease with serum magnesium level was statistically signicant at initial and at the end of intensive phase in PTB group. Conclusion: We concluded that decreased serum magnesium is a constant nding during pulmonary tuberculosis. In order to better understand the role of magnesium in pulmonary tuberculosis further clinical studies are required. Randomized controlled trials are warranted to generate higher levels of evidences to support our ndings.